Separators wood veneer

Electric road vehicles have been reduced to insignificance, as mentioned already by, vehicles with combustion engines. Another electric vehicle — the electrically driven submarine — presented a continuous challenge to lead-acid battery separator development since the 1930s and 1940s. The wood veneers originally used in electric vehicles proved too difficult to handle, especially if tall cells had to be manufactured. Therefore much intense effort took place to develop the first plastic separators. In this respect the microporous hard rubber separator, still available today in a more advanced version, and a micro-porous PVC separator (Porvic I) merit special mention 28]. For the latter a molten blend of PVC, plasticizer and starch was rolled into a flat product. In a lengthy pro-... 

The closest relative to the wood veneer surprisingly has retained some of its properties, which differentiate these separators from pure synthetic ones primarily, a positive effect in reducing the water loss in starter batteries [39, 70-72], This impact tends to decrease as the antimony content in the alloys is lowered, but it still represents an advantage over other leaf separators, unless a microporous pocket is required by the alloy anyway. 

In Europe, with the economic upswing after 1950, forklifts with batteries came into use - a development which met less acceptance in the U S A for various reasons, among them low fuel cost. In this appHcation rubber separators and microporous PVC (Porvic I) were finally able to replace wood veneers, until from around 1975 they again met strong competitors in the new separators aheady mentioned made of phenolic resin (DARAK), PVC, and mainly polyethylene (Daramic). Today this market is dominated by the polyethylene separator, as is shown in Table 11.4. The annual growth of this market is 2-3%, but with large fluctuation based on prevailing economic conditions. 

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